[go: up one dir, main page]

WO2001044634A1 - Moteur deux temps de balayage stratifie a pistons - Google Patents

Moteur deux temps de balayage stratifie a pistons Download PDF

Info

Publication number
WO2001044634A1
WO2001044634A1 PCT/JP2000/008788 JP0008788W WO0144634A1 WO 2001044634 A1 WO2001044634 A1 WO 2001044634A1 JP 0008788 W JP0008788 W JP 0008788W WO 0144634 A1 WO0144634 A1 WO 0144634A1
Authority
WO
WIPO (PCT)
Prior art keywords
scavenging
cylinder
port
piston
biston
Prior art date
Application number
PCT/JP2000/008788
Other languages
English (en)
Japanese (ja)
Inventor
Ryoji Zama
Takeshi Watanabe
Original Assignee
Komatsu Zenoah Co.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP35588499A external-priority patent/JP3828699B2/ja
Priority claimed from JP2000006859A external-priority patent/JP3828702B2/ja
Application filed by Komatsu Zenoah Co. filed Critical Komatsu Zenoah Co.
Priority to AU18875/01A priority Critical patent/AU1887501A/en
Priority to US10/149,410 priority patent/US6691650B2/en
Publication of WO2001044634A1 publication Critical patent/WO2001044634A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B17/00—Engines characterised by means for effecting stratification of charge in cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B25/00—Engines characterised by using fresh charge for scavenging cylinders
    • F02B25/14—Engines characterised by using fresh charge for scavenging cylinders using reverse-flow scavenging, e.g. with both outlet and inlet ports arranged near bottom of piston stroke
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B25/00—Engines characterised by using fresh charge for scavenging cylinders
    • F02B25/20—Means for reducing the mixing of charge and combustion residues or for preventing escape of fresh charge through outlet ports not provided for in, or of interest apart from, subgroups F02B25/02 - F02B25/18
    • F02B25/22—Means for reducing the mixing of charge and combustion residues or for preventing escape of fresh charge through outlet ports not provided for in, or of interest apart from, subgroups F02B25/02 - F02B25/18 by forming air cushion between charge and combustion residues
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
    • F02B33/02—Engines with reciprocating-piston pumps; Engines with crankcase pumps
    • F02B33/04—Engines with reciprocating-piston pumps; Engines with crankcase pumps with simple crankcase pumps, i.e. with the rear face of a non-stepped working piston acting as sole pumping member in co-operation with the crankcase
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
    • F02B33/02—Engines with reciprocating-piston pumps; Engines with crankcase pumps
    • F02B33/28—Component parts, details or accessories of crankcase pumps, not provided for in, or of interest apart from, subgroups F02B33/02 - F02B33/26
    • F02B33/30—Control of inlet or outlet ports
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
    • F02B33/44—Passages conducting the charge from the pump to the engine inlet, e.g. reservoirs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/18—Other cylinders
    • F02F1/22—Other cylinders characterised by having ports in cylinder wall for scavenging or charging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/02—Engines characterised by their cycles, e.g. six-stroke
    • F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
    • F02B2075/025—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F3/00—Pistons 
    • F02F3/24—Pistons  having means for guiding gases in cylinders, e.g. for guiding scavenging charge in two-stroke engines

Definitions

  • the present invention relates to a piston-valve stratified scavenging two-stroke engine, and more particularly to an arrangement of each cylinder port, a shape of a biston, and an improvement of a scavenging flow path.
  • stratified scavenging two-cycle engine As an example, International Publication No. WO 98/5703 There is what was disclosed in the issue. According to the same publication, as shown in Fig. 13, the scavenging port 12, leading air port 14, and exhaust port (not shown) are opened in the cylinder chamber 11 (the inner peripheral surface of the cylinder 10).
  • the cylinder 10 is provided with an intake port 15 for the air-fuel mixture connected to the crank chamber 3 and a scavenging flow path 16 connecting between the cylinder chamber 11 and the crank chamber 3:
  • Two leading air ports 14 are provided on the left and right sides of the intake port 15.
  • the leading air port 1.4 is provided at a position a predetermined distance away from the scavenging port 12 on the side of the cylinder chamber 3 in the axial direction of the cylinder 10, and is provided on the outer periphery of the piston 30a.
  • the scavenging port 12 and the leading air port 14 are connected via the provided bistone groove 34a, and air is supplied from the leading air port 14 to the scavenging flow path 16 via the scavenging port 12 during the suction stroke.
  • the piston lower edge 31 leads at the piston dead center position indicated by the solid line.
  • the piston upper edge 35 is located below the air port 14 and the piston upper edge 35 is located above the leading air port 14 at the piston bottom dead center position indicated by a thin two-dot chain line.
  • the piston lower edge 3 1 is a balance weight 2 provided on the crankshaft at the piston bottom dead center. 3 is set at the position closest to the crankshaft that does not interfere with the outer peripheral portion 2 3 a.
  • the lower port 31 of the piston Since the intake port 15 is provided alongside the leading air port 14 in the left-right direction, the lower port 31 of the piston has the intake port 15 and the crank chamber 3 at the piston top dead center.
  • a vertical groove 40 having a predetermined length F is provided in order to allow the fluid to communicate.
  • the inside of the cylinder chamber 11 is first scavenged by the leading air at the time of exhaust, the discharge of unburned gas due to the blow-by of the air-fuel mixture can be prevented, and the exhaust gas can be purified.
  • the lower part of the biston 31 and the upper part of the intake port 15 a A vertical groove 40 of length F is provided. Therefore, the lower edge 31 of the piston is located below the upper edge 15a of the intake port by a length F. As described above, at the bottom dead center of the piston, the upper edge 35 of the piston is located higher than the upper edge 15a of the intake port.
  • the lower edge 31 of the piston is the outer periphery of the balance shaft of the crankshaft 20. It is determined to be located above part 23 a.
  • FIG. 14 is a front sectional view of a second example of the conventional stratified scavenging two-cycle engine
  • FIG. 15 is a view taken along the line NN of FIG.
  • a cylinder 82 is mounted on the upper surface of the crankcase 81, and a biston 83 is inserted into the cylinder 82 in a sliding manner in the axial direction of the cylinder 82.
  • Crankcase 8 1 has a crankshaft 54 attached rotatably to it The piston 83 and the crankshaft 54 are connected by a connecting rod 55.
  • an exhaust port 60 opening to the cylinder chamber 56, a pair of scavenging ports 61, 61, and a pair of leading air ports 62, 62 are provided on the wall of the cylinder 82.
  • An air-fuel mixture port 63 is provided which opens to the air.
  • a pair of scavenging passages 90, 90 respectively connecting the pair of scavenging ports 51, 51 and the crank chamber 57 are provided in the side wall of the cylinder 82. Openings 91 and 91 are provided at the lower end of 90, respectively.
  • a pair of grooves 8 for connecting the pair of leading air ports 62, 62 and the pair of scavenging ports 61, 61 respectively near the piston top dead center are provided on the sides of the piston 83. 4, 84 are provided.
  • the opening / closing of the exhaust port 60, the scavenging ports 61, 61, the leading air ports 62, 62, and the mixture port 63 is performed by the vertical movement of the piston 83.
  • the leading air is sucked from the leading air ports 62, 62 and passes through the piston grooves 84, 84.
  • the scavenging channels 90, 90 are filled.
  • the fuel mixture is sucked into the crank chamber 57 from the mixture port 63.
  • the exhaust port 60 is opened to exhaust the exhaust gas, and then the scavenging ports 61, 61 are opened.
  • the pressure in the crank chamber 57 rises, leading air in the scavenging air passages 90, 90 flows into the cylinder chamber 56, and exhaust gas is discharged from the exhaust port 60 to the outside.
  • the air-fuel mixture inside flows through the scavenging passages 90, 90 and flows into the cylinder chamber 56 from the scavenging ports 61, 61. Accordingly, the amount of air-fuel mixture blow-through from the exhaust port 60 to the outside is reduced, and the exhaust gas is purified. However, the amount of the leading air is equal to the volume of the scavenging flow path 90, and the amount is insufficient.
  • FIG. 16 is a front sectional view of the stratified scavenging two-cycle engine described in the publication.
  • the cylinder 82 is mounted on the upper surface of the crankcase 85.
  • the scavenging port 61 is connected to the crank chamber 57 via a scavenging flow path 92.
  • Scavenging flow path 9 2 passes through the side wall of the cylinder 82, passes through the side wall of the crankcase 85, and communicates with an opening 93 provided at the bottom of the crank chamber 57.
  • the scavenging flow path 92 is long and large, the amount of leading air is sufficiently ensured, and blow-out of the air-fuel mixture is greatly reduced, thereby purifying the exhaust gas.
  • the present invention reduces the height of the engine by shortening the length of the biston in the cylinder axis direction, thereby reducing the field volume and weight, and ensuring a sufficient amount of leading air. It is intended to provide a stratified scavenging two-cycle engine that can reliably achieve exhaust gas purification.
  • the first invention of the biston valve type stratified scavenging two-stroke engine comprises a scavenging port, an exhaust port, and a leading air port which open on the inner wall of a cylinder attached to the upper part of the crankcase and are connected to the cylinder chamber.
  • An intake port for air-fuel mixture which is opened on the inner wall of the cylinder and connected to the crank chamber, a scavenging flow path connecting these scavenging boat and the crank chamber, and provided on the outer periphery of the piston. It has a biston groove connecting these scavenging ports and the leading air port during the suction stroke.
  • the scavenging port, exhaust port, leading air port, and intake port are opened and closed by the vertical movement of this piston.
  • a two-stroke scavenging valve of a stone-valve type wherein a lower edge of the leading air port is located closer to a crank chamber than an upper edge of the intake port; At the lower part of the piston facing the leading air boat, an extension is provided extending below the lower edge of the piston at the location facing the intake port of this piston, and this extension is attached to the web of the crankshaft. It is located outside the balance weight in the crankshaft direction, and has the above-mentioned bistone groove on its outer peripheral surface.
  • the lower edge of the leading air port is cranked from the upper edge of the intake port. Because it is located on the chamber side, the upper edge of the leading air port can be brought closer to the crank chamber side. Therefore, the position of the upper edge of the piston at the time of the piston's bottom dead center can be shifted toward the crankcase.
  • the lower edge of the biston which extends axially outside the balance shaft of the crankshaft, extends, and a piston groove is provided in this portion to connect the leading air boat and the scavenging port. Therefore, the lower edge of the piston can be lowered to a position where it does not interfere with the outer periphery of the balance weight at the time of the piston's bottom dead center. Therefore, the height of the biston from the upper edge of the biston to the lower edge of the biston can be reduced, so that a low-engine, light-weight, and low-cost layered scavenging two-cycle engine can be obtained.
  • a second invention is based on the configuration of the first invention, and has a configuration in which an upper edge of the intake boat and an upper edge of the leading air port are located at substantially the same height.
  • the upper edge of the biston at the time of the bottom dead center of the biston can be brought closer to the crank chamber side to the vicinity of the upper edge of the intake port, and the length of the piston in the cylinder axial direction can be shortened by one layer.
  • the length of the connecting rod can be shortened to lower the engine height, further reducing weight and reducing costs.
  • a scavenging port which opens into a cylinder chamber of a cylinder placed on the upper surface of a crankcase having a crank chamber formed therein, and which sucks and scavenges leading air taken in from the outside,
  • a biston valve type stratified scavenging two-cycle engine provided outside the side wall surface and having a scavenging passage communicating with the scavenging port and the crank chamber
  • a first scavenging passage provided outside the side wall surface of the cylinder and substantially parallel to an axis of the cylinder; and a first scavenging passage provided on an upper surface of the crankcase opposed to the first scavenging passage.
  • a second scavenging flow path that is provided so as to extend in a direction substantially perpendicular to the scavenging passage, and that has an opening at a terminal portion that communicates with the crank chamber; these openings and the second scavenging passage are A concave portion provided on the upper surface of the crankcase, a cylinder base surface of the cylinder in contact with the upper surface of the crankcase, a cylinder skirt portion at a lower portion of a side surface of the cylinder, and a second scavenging passage of the cylinder skirt portion. Whether the opposing part is close to or in contact with the bottom And a cylinder skirt extending portion extended so as to extend.
  • the second scavenging flow path provided with a concave portion on the upper surface of the crankcase is provided below the first scavenging flow path provided outside the cylinder wall surface and communicating with the scavenging port. Since the opening is provided at the end of the scavenging flow channel, a large scavenging flow channel volume can be secured. Therefore, a sufficient amount of leading air for scavenging can be secured, and exhaust gas purification can be reliably achieved.
  • the second scavenging flow path and its opening are formed by the concave portion provided on the upper surface of the crankcase, the cylinder base surface, the cylinder skirt portion, and the cylinder skirt extension portion, so that the structure is simplified. Moreover, because the crankcase can be made small and lightweight, a low-cost stratified scavenging two-cycle engine can be obtained.
  • a fourth invention is based on the configuration of the first invention, and further comprises: a first scavenging passage provided outside the side wall surface of the cylinder, substantially parallel to an axis of the cylinder, based on the configuration of the first invention.
  • a second scavenging flow path is provided on the upper surface of the crankcase opposite to the scavenging passage so as to extend in a direction substantially perpendicular to the first scavenging passage, and has an opening at the terminal portion communicating with the crank chamber.
  • the opening and the second scavenging passage are provided with a concave portion provided on the upper surface of the crankcase, a cylinder base surface of the cylinder in contact with the upper surface of the crankcase, and a cylinder skirt at a lower portion of a side surface of the cylinder. And a portion extending from the cylinder skirt portion of the cylinder skirt portion facing the second scavenging passage so as to approach or contact the bottom surface portion of the concave portion. It is a made configuration.
  • FIG. 1 is a front cross-sectional view of a stratified scavenging two-cycle engine according to a first embodiment of the present invention at the time of top dead center of a biston.
  • FIG. 2 is a side sectional view at the time of the top dead center of the biston in FIG.
  • FIG. 3 is a cross-sectional view of the cylinder taken along the line AA in FIG.
  • FIG. 4 is a side sectional view at the time of the bottom dead center of the biston in FIG.
  • FIG. 5 is a front view of the biston according to the first embodiment.
  • FIG. 6 is a view taken in the direction of the arrows BB in FIG.
  • FIG. 7 is a view taken in the direction of arrows C-C in FIG.
  • FIG. 8 is a development view taken along the line DD in FIG.
  • FIG. 9 is a front sectional view of a cylinder and a crankcase according to a second embodiment of the present invention.
  • FIG. 10 is a view taken in the direction of arrows K—K in FIG.
  • FIG. 11 is an L-L view of FIG.
  • FIG. 12 is a view taken along the arrow M— in FIG.
  • FIG. 13 is a side cross-sectional view of a cylinder portion of a stratified scavenging two-cycle engine according to a first conventional example.
  • FIG. 14 is a front sectional view of a stratified scavenging two-cycle engine according to a second conventional example.
  • FIG. 15 is a view of FIG.
  • FIG. 16 is a front sectional view of a stratified scavenging two-cycle engine according to a third conventional example.
  • FIG. 1 is a front cross-sectional view of a stratified scavenging two-cycle engine 1 according to the first embodiment
  • FIG. 2 is a side cross-sectional view thereof, showing a state at a piston top dead center position.
  • the cylinder 10 is attached to the upper part of the crankcase 2.
  • a piston 30 is slidably inserted in the cylinder 10 in the axial direction of the cylinder 10, forming a cylinder chamber 11 on the head side of the piston 30 and a crank chamber 3 on the bottom side.
  • the crankshaft 20 rotatably attached to the crankcase 2 via the bearing 4 and the biston 30 are connected by a connecting port 5.
  • a balance weight 23 is provided at a position opposite to the crankpin 22.
  • the outer peripheral portion 23a has an arc shape.
  • a scavenging port 12, an exhaust port 13, and a leading air port 14, which are connected to the cylinder chamber 11, are provided on the inner wall surface of the cylinder 10, and an intake port 1 for the air-fuel mixture, which is connected to the crank chamber 3. 5 are provided.
  • the cylinder 10 is provided with a scavenging flow path 16 connecting the scavenging port 12 and the crank chamber 3.
  • FIG. 3 is a cross-sectional view of the cylinder 10 and is a cross-sectional view taken along the line AA of FIG.
  • Two leading air ports 14 and 14 are provided on both sides of the intake boat 15, and the lower edges 14 b and 14 b of the leading air ports are connected to the upper edge 15 a of the intake port. Also, in the present embodiment, the upper edge 15a of the intake port and the upper edges 14a, 14a of the leading air port are located at the same height.
  • Scavenging ports 12 and 12 are provided at predetermined intervals above the leading air ports 14 and 14, and are connected to the scavenging channels 16 and 16, respectively.
  • Figure 4 is a cross-sectional side view of a stratified scavenging two-stroke engine at the bottom dead center of Biston.
  • the piston lower edge 31 is located at the position closest to the crankshaft 20 which does not interfere with the outer peripheral portions 23a, 23a of the two balance weights 23, 23 of the crankshaft 20, as in the conventional case. This part is located at the position facing the intake port 15 when the biston 30 moves up and down.
  • extension portions 32, 32 are provided extending below the lower edge 31 of the biston, and are provided on the outer peripheral portion of the extension portion 32.
  • Each has a piston groove 34.
  • the inner width W1 of the extending portion 32 is set to be larger than the outer width W2 in the crankshaft direction between the two balance weights 23, 23 of the crankshaft 20.
  • the interval W3 between the two leading air ports 14 and 14 shown in FIG. 3 is set to be larger than the inner width W1 of the extension 32.
  • the lower edge 33 of the extending portion is set at a position that does not interfere with the outer peripheral portion 6 a of the boss 6 in which the bearing 4 provided in the crank chamber 3 is provided.
  • the extension section 32 is provided at a position facing the leading air port 14 when the biston 30 moves up and down.
  • the piston groove 34 provided in the extension section 32 is formed as shown in FIG.
  • the scavenging port 12 and the leading air port 14 are connected at the position of the piston top dead center.
  • the upper edge 35 of the biston is located at the lower dead center of the piston, as shown in Fig. It is set so as to be located higher than the upper edge 14a of the air guide boat.
  • FIG. 5 is a front view of the piston 30, and FIG. 6 is a view taken in the direction of the arrows BB in FIG.
  • the lower end of the piston 30 is provided with an extension 32 extending below the lower edge 31 of the biston.
  • a piston groove 34 is provided on the outer peripheral surface of the extending portion 32.
  • the lower edge 31 of the piston is set at a position that does not interfere with the outer peripheral portion 23 a of the balance weight
  • the lower edge 33 of the extension portion is set at a position that does not interfere with the outer peripheral portion 6 a of the boss 6 of the crank chamber 3.
  • the height of the piston from the upper edge 35 of the piston to the lower edge 31 of the piston is H.
  • FIG. 7 is a view taken in the direction of arrows C-C in FIG.
  • An exhaust port 13 is provided on the opposite side of the intake port 15, and leading air ports 14 and 14 are provided on both sides of the intake port 15.
  • Scavenging boats 12 and 12 and scavenging passages 16 and 16 are provided on both sides perpendicular to the center line E—E connecting the intake boat 15 and the exhaust port 13.
  • the two piston grooves 34 and 34 connect the leading air ports 14 and 14 and the scavenging ports 16 and 16 respectively.
  • FIG. 8 is a development view taken in the direction of arrows D—D in FIG. 7, and shows the relationship between each port provided on the inner wall surface of the cylinder and the biston.
  • the solid lines show the scavenging boats 12 and 12 provided on the inner wall surface of the cylinder 10, the exhaust boat 13, the leading air ports 14 and 14, and the intake port 15.
  • the thin dashed lines indicate the upper edge 35, the lower edge 31 of the biston at the top dead center position, and the biston groove 34, and the thin two-dot chain line indicates the upper edge 35 of the biston at the bottom dead center position and below the biston. Edges 31 are shown respectively.
  • the piston groove 34 connects the leading air port 14 and the scavenging port 12.
  • the lower biston edge 31 is located above the intake port 15. Also, at the bottom dead center position of the piston, the upper edge 35 of the piston is located below the scavenging boat 12 and the exhaust port 13 and above the leading air port 14 and the intake port 15. ing. At this time, the distance from the upper edge 35 of the piston to the lower edge 31 of the piston is the height H of the biston shown in FIG.
  • the height of the piston 30 can be reduced.
  • the fixed piston shown in Fig. 13 The position of the intake boat 15 and the leading air port 14 is shifted toward the crankcase 3 by the length F, and the position of the upper edge 35 of the piston is shifted toward the crankcase 3 by the length F, compared to the length 30a. Can be shifted.
  • the height of the piston according to the present embodiment is H
  • the height of the conventional piston is “H + F”
  • the height can be reduced by the length F.
  • the connecting rod 5 can be shortened, so that a low-profile, lightweight, and low-cost layered scavenging two-cycle engine can be obtained.
  • FIG. 9 is a front sectional view of a cylinder and a crankcase according to the second embodiment
  • FIG. 10 is a view taken in the direction of arrows AA in FIG.
  • a cylinder 52 is mounted on the upper surface 58 of the crankcase 51 with the cylinder base surface 66 in contact with it.
  • An exhaust port 60, a pair of scavenging ports 61, 61, a pair of leading air ports 62, 62, and a mixture port 63 are opened on the inner wall of the cylinder 52.
  • a pair of first scavenging flow paths 71, 71, which communicate with the scavenging ports 61, 61 at the top and have openings at the bottom, are provided parallel to the cylinder axis. Have been killed.
  • the upper surface 58 of the crankcase 51 communicates with the lower openings of the pair of first scavenging passages 71, 71, respectively, and is substantially perpendicular to the first scavenging flow passages 71, 71.
  • the scavenging flow path 70 includes first and second scavenging flow paths 71 and 72.
  • FIG. 11 is a view taken along the line L-L in FIG. 9 and shows the shape of the concave portion 64 formed on the upper surface 58 of the crankcase.
  • a cylinder scar extension portion 68 is provided at a portion of the cylinder portion 67 facing the second scavenging flow path 72 of the contact portion 67, and a tip portion thereof is close to a bottom portion 65 of the recess portion 64. Or is in contact. That is, the second scavenging flow channel 72 is formed by the concave portion 64, the cylinder base surface 66, the cylinder skirt portion 67, and the cylinder scar extending portion 68.
  • the opening 73 is formed by a recess 64, a cylinder base surface 66, and a cylinder scar extension portion 68, as shown in FIG. Since the scavenging flow path 70 of the stratified scavenging two-cycle engine according to the present embodiment is constituted by the first and second scavenging flow paths 71 and 72, the volume of the second scavenging flow path 72 is larger than that of the conventional one. As a result, exhaust gas purification can be surely achieved by increasing the amount of leading air.
  • the second scavenging flow path 72 and the opening 73 are formed by a concave portion 64 provided on the upper surface 58 of the crankcase 5, a cylinder base surface 66, a cylinder skirt portion 67, and a cylinder skirt extension portion. 6 and 8, the structure is simple, and the thickness of the side wall of the crankcase 51 can be made thinner than in the case where a scavenging flow path is provided in the side wall of the conventional crankcase 51. Therefore, the size and weight can be reduced and the cost can be reduced. Industrial applicability
  • the present invention is useful as a stratified scavenging two-cycle engine that has a low engine height, is lightweight, and can reliably achieve exhaust gas purification.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Cylinder Crankcases Of Internal Combustion Engines (AREA)

Abstract

L'invention concerne un moteur deux temps de balayage stratifié à pistons présentant une hauteur, un poids et un encombrement réduits, et pouvant diminuer efficacement l'émission des gaz d'échappement. Pour ce faire, le bord supérieur (14a) d'un orifice d'air pilote (14) formé dans la paroi intérieure d'un cylindre (10) est approximativement au même niveau que le bord supérieur (15a) d'un orifice d'admission (15). A l'extrémité inférieure d'un piston (30) opposé à l'orifice d'air pilote (14), des saillies (32) s'étendent vers le bas au-delà du bord inférieur (31) du piston opposé à l'orifice d'admission (15). L'espacement (W1) entre la saillie de droite (32) et celle de gauche (32) est plus grand que la largeur extérieure (W2) d'une masse d'équilibrage (23) sur un arbre à vilebrequin (20). Une gorge du piston (34) est creusée dans la surface périphérique extérieure de la saillie (32) pour faire communiquer l'orifice d'air pilote (14) et un orifice de balayage (12) pendant la course d'aspiration. De plus, un second canal d'écoulement de balayage (72), de construction simple, est ménagé au-dessous d'un premier canal d'écoulement de balayage (71).
PCT/JP2000/008788 1999-12-15 2000-12-13 Moteur deux temps de balayage stratifie a pistons WO2001044634A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU18875/01A AU1887501A (en) 1999-12-15 2000-12-13 Piston valve type layered scavenging 2-cycle engine
US10/149,410 US6691650B2 (en) 1999-12-15 2000-12-13 Piston valve type layered scavenging 2-cycle engine

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP35588499A JP3828699B2 (ja) 1999-12-15 1999-12-15 ピストンバルブ式層状掃気２サイクルエンジン
JP11/355884 1999-12-15
JP2000-006859 2000-01-14
JP2000006859A JP3828702B2 (ja) 2000-01-14 2000-01-14 層状掃気２サイクルエンジンの掃気通路

Publications (1)

Publication Number Publication Date
WO2001044634A1 true WO2001044634A1 (fr) 2001-06-21

Family

ID=26580347

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2000/008788 WO2001044634A1 (fr) 1999-12-15 2000-12-13 Moteur deux temps de balayage stratifie a pistons

Country Status (3)

Country Link
US (1) US6691650B2 (fr)
AU (1) AU1887501A (fr)
WO (1) WO2001044634A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2840023A1 (fr) * 2002-05-24 2003-11-28 Stihl Ag & Co Kg Andreas Moteur a deux temps
US6668770B2 (en) 2000-01-14 2003-12-30 Aktiebolaget Electrolux Two-stroke interal combustion engine
US6668771B2 (en) 2000-01-14 2003-12-30 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6712029B1 (en) 1999-01-19 2004-03-30 Lars Andersson Cylinder for an internal combustion engine
US6718917B2 (en) 2000-04-27 2004-04-13 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6877723B2 (en) 2000-01-14 2005-04-12 Aktiebolaget Electrolux Valve for control of additional air for a two-stroke engine
US7082910B2 (en) 1999-01-19 2006-08-01 Aktiebolaget Electrolux Two-stroke internal combustion engine
CN102162395A (zh) * 2010-02-17 2011-08-24 安德烈亚斯·斯蒂尔两合公司 两冲程发动机
DE202012101133U1 (de) * 2012-03-29 2013-07-01 Makita Corporation Brennkraftmaschine, insbesondere 2-Takt-Brennkraftmaschine
DE10223070B4 (de) * 2002-05-24 2015-10-08 Andreas Stihl Ag & Co. Zweitaktmotor

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10222346B4 (de) * 2002-05-21 2013-10-17 Andreas Stihl Ag & Co. Harter Verbindungskanal
DE10223069A1 (de) * 2002-05-24 2003-12-11 Stihl Maschf Andreas Zweitaktmotor
EP1550799B1 (fr) * 2002-10-11 2007-04-04 Kawasaki Jukogyo Kabushiki Kaisha Moteur a deux cycles du type a balayage d'air
US7331315B2 (en) * 2005-02-23 2008-02-19 Eastway Fair Company Limited Two-stroke engine with fuel injection
US20060243230A1 (en) * 2005-03-23 2006-11-02 Mavinahally Nagesh S Two-stroke engine
DE102010045017B4 (de) 2010-09-10 2020-08-06 Andreas Stihl Ag & Co. Kg Zweitaktmotor
JP6487631B2 (ja) 2014-05-21 2019-03-20 株式会社やまびこ 層状掃気式２サイクル内燃エンジン
SE543272C2 (en) 2019-03-06 2020-11-10 Husqvarna Ab Engine piston, engine, hand-held tool, and method of manufacturing an engine piston
WO2022236479A1 (fr) * 2021-05-08 2022-11-17 永康市茂金园林机械有限公司 Tuyau d'entrée d'air d'un moteur à deux temps à balayage stratifié
CN113107662A (zh) * 2021-05-08 2021-07-13 永康市茂金园林机械有限公司 一种用于分层扫气二冲程发动机的汽缸活塞单元

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS51160721U (fr) * 1975-06-14 1976-12-21
JPS58146822U (ja) * 1982-03-29 1983-10-03 株式会社クボタ ２サイクルエンジンの掃気装置

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS585423A (ja) 1981-06-30 1983-01-12 Nippon Clean Engine Res クランク室圧縮２サイクル内燃機関
JPS58146822A (ja) 1982-02-24 1983-09-01 Kawasaki Heavy Ind Ltd コ−ルパイプ内の石炭層レベル検知方法
DE19543065C2 (de) * 1995-11-09 2002-10-31 Gag Bioscience Gmbh Zentrum Fu Verfahren zur Genomanalyse und Mittel zur Durchführung des Verfahrens
DE69820443T2 (de) 1997-06-11 2004-10-07 Komatsu Zenoa Kk Schichtspülung für zweitaktmotoren
DE19754482A1 (de) * 1997-11-27 1999-07-01 Epigenomics Gmbh Verfahren zur Herstellung komplexer DNA-Methylierungs-Fingerabdrücke

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS51160721U (fr) * 1975-06-14 1976-12-21
JPS58146822U (ja) * 1982-03-29 1983-10-03 株式会社クボタ ２サイクルエンジンの掃気装置

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7574984B2 (en) 1999-01-19 2009-08-18 Husqvarna Ab Two-stroke internal combustion engine
US7025021B1 (en) 1999-01-19 2006-04-11 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6712029B1 (en) 1999-01-19 2004-03-30 Lars Andersson Cylinder for an internal combustion engine
US7082910B2 (en) 1999-01-19 2006-08-01 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6668771B2 (en) 2000-01-14 2003-12-30 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6877723B2 (en) 2000-01-14 2005-04-12 Aktiebolaget Electrolux Valve for control of additional air for a two-stroke engine
US6668770B2 (en) 2000-01-14 2003-12-30 Aktiebolaget Electrolux Two-stroke interal combustion engine
US6718917B2 (en) 2000-04-27 2004-04-13 Aktiebolaget Electrolux Two-stroke internal combustion engine
US6895910B2 (en) 2002-05-24 2005-05-24 Andreas Stihl Ag & Co. Kg Two-cycle engine having scavenging
FR2840023A1 (fr) * 2002-05-24 2003-11-28 Stihl Ag & Co Kg Andreas Moteur a deux temps
DE10223070B4 (de) * 2002-05-24 2015-10-08 Andreas Stihl Ag & Co. Zweitaktmotor
DE10321571B4 (de) * 2002-05-24 2016-01-07 Andreas Stihl Ag & Co. Kg Zweitaktmotor mit Spülvorlage
DE10362403B3 (de) * 2002-05-24 2021-02-04 Andreas Stihl Ag & Co. Kg Zweitaktmotor mit Spülvorlage
CN102162395A (zh) * 2010-02-17 2011-08-24 安德烈亚斯·斯蒂尔两合公司 两冲程发动机
DE202012101133U1 (de) * 2012-03-29 2013-07-01 Makita Corporation Brennkraftmaschine, insbesondere 2-Takt-Brennkraftmaschine

Also Published As

Publication number Publication date
AU1887501A (en) 2001-06-25
US6691650B2 (en) 2004-02-17
US20030140874A1 (en) 2003-07-31

Similar Documents

Publication Publication Date Title
WO2001044634A1 (fr) Moteur deux temps de balayage stratifie a pistons
JP3313373B2 (ja) 層状掃気２サイクルエンジン
EP2327864B1 (fr) Moteur à deux temps, à balayage, stratifié
JP3079046B2 (ja) 層状掃気２サイクルエンジン
US20090095269A1 (en) Two-Cycle Engine
US9816431B2 (en) Stratified scavenging two-cycle engine
CA1248027A (fr) Moteur a combustion interne deux temps avec reniflard
WO2008004449A1 (fr) Moteur à deux temps à balayage stratifié
US7322322B2 (en) Stratified-scavenging two-stroke internal combustion engine
US6450135B1 (en) Two-stroke internal combustion engine
JP3703924B2 (ja) ２サイクル内燃エンジン
JP4342960B2 (ja) ２サイクルエンジン
JP2000320338A (ja) ２サイクル内燃エンジン
US6874455B2 (en) Two-cycle engine
JP3773507B2 (ja) ２サイクル内燃エンジン
JP2001173447A (ja) ピストンバルブ式層状掃気２サイクルエンジン
JP2002332847A (ja) 層状掃気２サイクルエンジン
JPH09242546A (ja) クランク室予圧縮型火花点火式２ストローク内燃機関
JP3932267B2 (ja) ２サイクルエンジン
JP2001193466A (ja) 層状掃気２サイクルエンジンの掃気通路
JPH0721873Y2 (ja) ２サイクルエンジン
JP2024151894A (ja) 内燃機関のオイル分離装置
JP2002332846A (ja) 層状掃気２サイクルエンジン
JP2007285219A (ja) ２サイクルエンジン
JP2004257371A (ja) 時間差掃気２サイクルエンジン

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA CN US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): DE FR GB IT SE TR

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 10149410

Country of ref document: US

122 Ep: pct application non-entry in european phase